I adopted my cat about two years ago when she was about 3 months old. She did not receive the vaccine for Feline Leukemia because she was to be a strictly indoors cat. She escaped one day and didn't come back until the next day with bite marks, she had gotten into a fight with another cat. At her check up we discovered that she has feline leukemia. About a month after her diagnosis she has had some terrible behavior issues. She is no longer affectionate and wants to simply be left alone ( i can only assume its because she might be in pain). She eats well and has a healthy fur coat the only real vi sable sign that she might not be doing well is that her gums and toung are almost white. My problem is that she has become unfriendly to my children as to where they are use to her loving them and she loves to scratch my furniture. I can not just give her to the humane society because she has feline leukemia and I don't know any one who will take her. Should I put her to sleep?

That's a really tough one. Feline leukemia is such a horrible disease and to this day I wonder if I did the right thing caring for my cats until the end. I cared for two cats with feline leukemia. There was times when they did better and it is my understanding that feline leukemia can go into remission. I know that some cats can have it and never show any symptoms. I think I hung on to this hope.
20/20 hindsight I think the one cat was in pain more than I realized while the other showed no symptoms other than the white gums. Neither cat lived a full live. I think now that I probably should have put down the cat who was in pain. Your cat shows some symptoms and aggression which indicates he is already in pain. In the end he will probably come down with an infection his body will not be able to fight. Both of my cats had beautiful coats to the end despite of being very sick.
If you think he is suffering I think you should put him down but only you can make that decision when the time will be right.
You also have 2 small children to think about and I do not know if your children are old enough to understand and get used to the fact that the kitty is not feeling well and does not want to be loved.
The humane society will not take a cat with feline leukemia just because it will pose a risk to all the other cats sheltered there. Your vet will probably advise you to put the cat to sleep as well.
My heart goes out to you.

Feline leukemia signals one issue, and that is making sure no infections are left unchecked. It is not a death sentence, but more of a monitoring issue to make sure she stays as healthy as possible.

She can live many years with careful care. If she is not feeling well, she may not be particularly friendly so see if there is a heath problem. The description of her gums and tongue suggests a problem, which can be managed, through assistance from your vet.

See if the Vet can do anything to treat your cat first. If they can't then it doesn't necessarily mean that your cat will die from it. There's a chance that your cat could fight it off. For more information you could look at http://en.wikipedia.org/wiki/Feline_leukemia_virus and then any citations it gives at the bottom of the article. But yes, if it were me I would keep her as long as I could and try to make her comfortable, until it would be cruel not to put her to sleep I mean.

If her gums and tongue are almost white, she is anemic and ill. That's why she's so ill-tempered, she doesn't feel well! Take her to the vet and get her treated, there is no reason to put a FeLV cat down as most of their issues can be treated, same as in a cat that is not FeLV positive. You really need to give her a chance, and get her to the vet. Just putting her to sleep isn't really a very good option, if she's got an issue that can be treated. Cats can live healthy and happy lives with FeLV, it's not something they need to automatically be put to sleep for. And no, taking her to a shelter isn't an option as she'll be euthanized as soon as you turn and walk out the door, since FeLV is highly contagious especially in a shelter environment.